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41.
The history and findings in a patient with erythroleukaemia who developed a fungal brain abscess during the agranulocytic phase of induction treatment is reported. The radiological features of fungal infection are reported, with emphasis on the importance of clinical judgement in making the diagnosis. The autopsy findings further illustrate the increasing importance of this previously very rare condition.  相似文献   
42.
In a selected group of 8 patients with progressive alopecia areata (AA) leading to AA universalis, immunological aspects (in the peripheral blood and the tissue) were studied during the period of the intitial attack of the disease. The peripheral T-cell helper/suppressor ratio appeared not to be a reliable parameter for the disease activity. The intrabulbar and peribulbar distribution of T-cells, Langerhans cells and of HLA-DR expression in and around the anagen hair follicles in the progressive areas of the disease (region of exclamation-mark hairs) may suggest a T-cell-mediated injury primarily in the peribulbar regions of the follicles. The data presented tend to support the possibility that in the early development of AA, the dermal pailla (capillary network?) may be the prime target of immunologic injury.  相似文献   
43.
Numerous interrelated metabolic and morphological variables such as plasma insulin levels, glucose tolerance and abdominal obesity are associated with changes in plasma lipoprotein levels. The present study was undertaken to differentiate, using a multivariate approach, the respective contributions of plasma glucose and insulin levels, obesity and regional adipose tissue distribution to the variance in plasma lipoproteins. The study group was composed of 69 healthy premenopausal women (age 35.4 +/- 5.0 years (mean +/- s.d.); percent body fat 40.7 +/- 10.1). Indices of carbohydrate metabolism showed significant univariate correlations with triglyceride (TG) and/or cholesterol (CHOL) content of plasma VLDL, LDL and HDL (P less than 0.05). Multivariate analyses indicated that the explained variance in plasma VLDL-TG (R2 x 100 = 44 percent, P less than 0.05) and LDL-apoprotein (apo) B levels (R2 x 100 = 33.1 percent, P less than 0.08) was entirely accounted for by indices of carbohydrate metabolism and body fat distribution, whereas total body fatness added no significant contribution to these models. Multivariate analyses also revealed that the best possible regression model to predict the variation in plasma HDL2-CHOL levels only included computed tomography-derived deep abdominal adipose tissue area (P less than 0.0001). All other variables were unable to further improve the explained variance in plasma HDL2-CHOL levels. In partial correlation analyses, indices of carbohydrate metabolism and the waist-to-hip circumference ratio (WHR) remained significantly correlated with plasma VLDL-TG and LDL-apo B levels after adjustment of VLDL-TG and LDL-apo B for either insulin and glucose levels, or for the WHR (P less than 0.08). After correcting for deep abdominal fat accumulation, no significant correlation was observed between indices of carbohydrate metabolism and plasma HDL2-CHOL levels whereas deep abdominal fat showed significant correlations with HDL2-CHOL levels (P less than 0.05) after correction for indices of carbohydrate metabolism. These results suggest that both disturbances in glucose-insulin homeostasis and abdominal obesity are significantly associated with changes in plasma VLDL-TG and LDL-apo B levels and that these associations are partly independent from each other. These results also indicate that mechanisms other than disturbances in glucose homeostasis and hyperinsulinemia are responsible for the association between the level of deep abdominal fat and plasma HDL2-CHOL levels.  相似文献   
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45.
Endovascular expanding metallic stents were percutaneously implanted in the iliac arteries and veins of pigs. The vessels had been stenosed by a ligature of catgut 4 weeks prior to this. Platelets were labeled with Indium 111 and the deposition onto the dilated and stented areas was dynamically registered for 240 min with a scintillation camera. All six arterial and six venous stents remained patent throughout the examination period. At the site of arterial stenting there was an increase, of deposited activity, and in the veins a decrease. These experimental findings support the use of endovascular stents after dilation, especially in venous stenoses.  相似文献   
46.
47.
 The cercarial emergence rhythms of Schistosoma mansoni were analyzed for mixed infection of the snail Biomphalaria glabrata with two chronobiological strains, one with an early shedding pattern and the other with a late shedding pattern. Under these conditions, each parasite strain kept its own circadian cercarial emergence pattern. When the chronobiological variants were of the same species, no interference between the trematode larvae occurred during the cercarial emergence process. These results confirm that within the host-parasite system the parasite component is directly responsible for the cercarial emergence pattern. Received: 16 September 1996 / Accepted: 18 October 1996  相似文献   
48.
Summary Preliminary results obtained from 26 cases of prolactinomas less than 20 mm in diameter after treatment by enlarged adenomectomy are described.The operation consisted in removal of the adenoma, a layer of normal pituitary at the outer edge of the tumour and the pituitary capsule in contact with the sellar meninges. 24 women and 2 men were involved whose prolactin levels (PRL) were less than 200 ng/ ml. All presented abnormal PRL responses to Thyrotropin releasing hormone (TRH) and Metoclopramide (MCP) tests and an absence of a nocturnal rise in the sleep cycle study. Postoperatively, three patients developed transitory diabetes insipidus and five transitory adrenal insufficiency. Gonadotropin reserve was always found normal. All 24 women resumed normal menstrual cycles and two became pregnant within one year. From a serological viewpoint, after surgery 100% of patients were found to be normal for levels of prolactin but only 85% turned to normal dynamic tests. The results of this small series of enlarged adenomectomies seem better than those obtained using selective adenomectomy, but must be confirmed with time.  相似文献   
49.
The cholinergic receptors in rabbit isolated rectus muscle preparations were characterized by means of cholinergic agonists and antagonists. The concentration-dependent contraction induced by acetylcholine, carbachol or oxotremorine remained uninfluenced by atropine (10(-5) M), whereas the nicotinic receptor antagonist hexamethonium caused a parallel shift of the concentration-response curve. The agonists pilocarpine, methacholine and aceclidine, which are selective muscarinic receptor stimulants, did not cause contraction of the muscle preparation. However, the nicotinic receptor stimulant 1,1-dimethyl-4-phenylpiperazine iodide (DMPP) caused contraction similar to that induced by acetylcholine. DMPP-induced contractions were inhibited by hexamethonium, causing a parallel rightward shift of the concentration-response curve. This shift could be quantified by means of a Schild plot, indicating competitive antagonism with a PA2 value of 4.63 for hexamethonium. Atropine when applied together with hexamethonium did not cause a further shift of the concentration-response curve. The present results clearly indicate that the cholinergic receptors which mediate contraction in the rabbit isolated extraocular muscle preparation belong to the nicotinic subtype.  相似文献   
50.
Zusammenfassung Experimentelle Untersuchungen haben für den maschinellen Bronchusverschluß nach Lobektomie und Pneumonektomie im Vergleich zu anderen Nahtmaterialien die geringste Entzündungsrate und die höchste Zugfestigkeit ergeben. In einer konsekutiven Serie von 233 Lungenresektionen der Chirurgischen Kliniken Köln-Lindenthal und der Klinik für Allgemein- und Abdominalchirurgie der Johannes Gutenberg-Universität Mainz ging die Häufigkeit einer Bronchus-stumpfinsuffizienz von 7,1% nach manuellem Bronchusverschluß auf 2,0% und die insuffizienzbedingte Letalität auf 0,7% bei Anwendung des Klammergeräts zurück. Die wesentlichen Vorteile des maschinellen Bronchusverschlusses sind die Einfachheit der Anwendung, die Schnelligkeit und die Gleichmäßigkeit des Verschlusses. Damit stellen die Klammernahtgeräte bei Lungenresektionen eine wertvolle Ergänzung der Operationstechnik dar.
Mechanical and manual bronchial closure —results of a consecutive trial
Summary After lobectomy and pneumonectomy in experimental evaluations stapled bronchial closures showed the lowest incidence of inflammatory reaction and the highest strength determined by leakage pressure compared with other suture material. A total of 233 lung resections - performed at Surgical University Clinic Köln-Lindenthal and the Clinic for General and Abdominal Surgery of the Johannes-Gutenberg-Universität Mainz — were reviewed. Mechanical stapling reduced the rate of bronchopleural fistulas to 2.0% compared with 7.1 % after manual suturing. In parallel, mortality related to bronchial stump leakage decreased to 0.7%. Main advantages of bronchial closure with staplers are the simplicity of their use, the speed and the uniformity of the closure. Thereby stapling devices are valuable completions in pulmonary surgery.
  相似文献   
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